Rapidcreekite from Rapid Creek, Yukon . Held in the A. E. Seaman Mineral Museum . — Photo: Chris857 · CC BY-SA 3.0
Rapidcreekite
A white hydrated calcium sulfate-carbonate discovered in 1983 in northern Yukon.
Intro adapted from Wikipedia (CC BY-SA).
Rapidcreekite is an IMA-recognized mineral species in the sulfate class, with the chemical formula Ca₂(SO₄)(CO₃)·4H₂O.
It crystallizes in the orthorhombic crystal system (space group Pcnb).
Key properties: Mohs hardness 2; specific gravity 2.21; White streak; Vitreous luster; refractive index 1.522; optically biaxial.
IMA symbol Rck, IMA status: approved, named in 1984.
A rare secondary mineral formed along joint and bedding-plane surfaces of quartz-rich sideritic iron formation.
It is found associated with Kulanite, gypsum, aragonite.
The name refers to its occurrence in the Rapid Creek district, Canada.